In order to utilize a light emitting element which emits diffuse light, such as an LED, for the purpose of illumination, a technique for endowing light emitted from the light emitting element with directivity for efficient illumination is known. In one example shown in FIG. 25, a reflection surface 2 is disposed near a top surface 1A of a light emitting element 1 to guide light from the light emitting element 1 through a sealing resin (transparent member) 31 onto an incident surface 3 adjacent to a light guide unit.
In one specific example of such a technique that has been proposed, a light emitting element is covered by a reflection surface with differences in refractive index or a mirror reflection surface to efficiently supply light to an optical fiber (refer to, for example, Patent Documents 1 and 2).
Another example has also been proposed where a light source is covered with a reflection chamber having an opening so that light from the opening is emitted along a tapered light guide member to improve directivity (refer to, for example, Patent Document 3).
Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2003-101077
Patent Document 2: Japanese Unexamined Patent Application, Publication No. Hei 10-84137
Patent Document 3: Japanese Unexamined Patent Application, Publication No. Hei 7-98416